Various medical procedures, particularly cardiology procedures, involve accessing a corporeal vessel or other lumen through a percutaneous sheath. Access to the vessel necessarily requires the formation of a hole or puncture in the vessel wall so that a medical procedure can be performed. After the particular medical procedure has been performed, the sheath and other tools must eventually be removed from the vessel and the access hole in the vessel wall must be closed.
Therefore, a number of closure devices have been developed to close the hole in the vessel wall. Examples of prior vascular puncture closure devices are described in U.S. Pat. Nos. 6,179,863; 6,090,130; and 6,045,569 and related patents that are hereby incorporated by reference. The closure devices disclosed in the above-referenced patents and others are intended to seal an arteriotomy with an absorbable anchor and a collagen sponge. The anchor and the collagen sponge are held together with a self-tightening slip knot at the arteriotomy by a length of absorbable suture. The anchor and collagen sponge are cinched together across the arteriotomy, creating a sandwich-like effect. In order to seal the hole, it is necessary to apply a compressive sealing force to the arteriotomy, which is normally supplied by the slip-knotted suture. However, if the collagen sponge does not position correctly over the hole, there is potential for bleeding. The prior designs for the collagen sponge are generally rectangular, and have a three-hole or five-hole weave pattern allowing the collagen sponge to corkscrew through the puncture tract as the suture is pulled. However, the size of the rectangular-shaped collagen sponge is limited, because the collagen sponge must fit inside a carrier tube of the tissue puncture closure device.
Because of the limited size and surface area available for the standard rectangular-shaped collagen sponge, sometimes the hole in the vessel is not completely covered or adequately sealed. If the hole is not adequately sealed, residual bleeding may occur, resulting in an extended period of time to reach hemostasis. Therefore, there is a need to provide better coverage at a tissue puncture site to cover a wider area at arterial or other punctures.